linux-stable.git/drivers/block/drbd/drbd_req.c, branch linux-3.16.y

drbd: merge_bvec_fn: properly remap bvm->bi_bdev

2015-01-05T13:48:41+00:00

commit 3b9d35d744bb5139f9fed57f38c019bb8c7d351c upstream.

This was not noticed for many years. Affects operation if
md raid is used a backing device for DRBD.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Luis Henriques

drbd: evaluate disk and network timeout on different requests

2014-04-30T19:46:55+00:00

Just because it is the oldest not yet completed request
does not make it the oldest request waiting for disk.
Or waiting for the peer.

And we completely missed already completed requests
that would still hold references to activity log extents,
waiting only for the barrier ack.

Find two oldest not yet completely processed requests,
one that is still waiting for local completion,
and one that is still waiting for some response from the peer.
These may or may not be the same request object.

Then separately apply the network and disk timeouts, respectively.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe

drbd: add back some fairness to AL transactions

2014-04-30T19:46:55+00:00

When batching more updates to the activity log into single transactions,
we lost the ability for new requests to force themselves into the active
set: all preparation steps became non-blocking, and if all currently
hot extents keep busy, they could starve out new incoming requests
to cold extents for quite a while.

This can only happen if your IO backend accepts more IO operations per
average DRBD replication round trip time than you have al-extents
configured.

If we have incoming requests to cold extents,
at least do one blocking update per transaction.

In an artificial worst-case workload on SSD with an asynchronous 600 ms
replication link, with al-extents = 7 (the minimum we allow), and
concurrent full resynch, without this patch, some write requests have
been observed to be starved for 40 seconds.
With this patch, application observed a worst case latency of twice the
replication round trip time.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe

drbd: prepare sending side for REQ_DISCARD

2014-04-30T19:46:55+00:00

Note that I do NOT call __drbd_chk_io_error for failed REQ_DISCARD.
That may be wrong, though, or needs to differ between EOPNOTSUPP and
other errors...

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe

drbd: Create a dedicated struct drbd_device_work

2014-02-17T15:50:39+00:00

drbd_device_work is a work item that has a reference to a device,
while drbd_work is a more generic work item that does not carry
a reference to a device.

All callbacks get a pointer to a drbd_work instance, those callbacks
that expect a drbd_device_work use the container_of macro to get it.

Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Philipp Reisner

drbd: Move conf_mutex from connection to resource

2014-02-17T15:46:46+00:00

Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Philipp Reisner

drbd: Add explicit device parameter to D_ASSERT

2014-02-17T15:45:04+00:00

The implicit dependency on a variable inside the macro is problematic.

Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Philipp Reisner

drbd: Remove the terrible DEV hack

2014-02-17T15:45:01+00:00

DRBD was using dev_err() and similar all over the code; instead of having to
write dev_err(disk_to_dev(device->vdisk), ...) to convert a drbd_device into a
kernel device, a DEV macro was used which implicitly references the device
variable.  This is terrible; introduce separate drbd_err() and similar macros
with an explicit device parameter instead.

Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Philipp Reisner

drbd: Introduce "peer_device" object between "device" and "connection"

2014-02-17T15:44:51+00:00

In a setup where a device (aka volume) can replicate to multiple peers and one
connection can be shared between multiple devices, we need separate objects to
represent devices on peer nodes and network connections.

As a first step to introduce multiple connections per device, give each
drbd_device object a single drbd_peer_device object which connects it to a
drbd_connection object.

Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Philipp Reisner

drbd: Rename drbd_tconn -> drbd_connection

2014-02-17T15:44:47+00:00

sed -i -e 's:all_tconn:connections:g' -e 's:tconn:connection:g'

Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Philipp Reisner